DESCRIPTION: (Adapted from the Applicant's Abstract.) The long-term objective of this proposal is to provide a clearer understanding of the receptive communication problems concomitant with normal and abnormal aging processes. This goal will be achieved through investigations in which patterns of perceptual errors are examined relative to cognitive, sensory, and acoustic factors leading to a clearer understanding of the aging auditory system and its processes, and ultimately to better diagnostic, intervention and rehabilitation techniques and strategies. There are three multi-faceted experiments proposed; each examines a different aspect of speech perception and the aging auditory system. Cumulatively these data will form a basis for modeling perceptual speech errors for the aging listener; presbycusis will be a significant focal point of each of the proposed studies. The specific aims of each study are: 1) To study the relative use of contextual and acoustical cues by the elderly; 2) To examine the effects of information transmission rate and input capacity (time compression) and its role in types of errors that are produced for elderly listeners; 3) To observe perceptual errors stemming from short-term, or working memory processes and encoding limitations.